My War of 1812 Chronicles featured a post about William Gray Simms. There were Simms related to Blackburns who were related to Blacks in Abingdon, Washington County, Virginia.
Tyler's quarterly historical and genealogical magazine, Volumes 1-2:
"The widow of Lieutenant William Blackburn, Elizabeth (Black) Blackburn, her brother, Capt. Joseph Black and John Blackburn were granted letters of administration on the estate of Lieutenant William Blackburn November 24th 1780, they, together with Samuel Newell and John Davis... ."